Adhesive composition and articles made therefrom

Abstract

An adhesive composition comprising from about 2 to about 10 wt. % multifunctional ethylenically unsaturated siloxane polymer, from about 2 to about 10 wt. % monofunctional ethylenically unsaturated siloxane macromer, and from about 85 to about 96 wt. % vinyl monomer is described. The adhesive composition is used to make adhesive articles that, when applied to a substrate, remain removable or repositionable, even after long periods of time. The adhesive composition may be used in transfer adhesive films, and in laminated articles suitable for use in optical applications.

What is claimed is: 
     
       1. An adhesive composition comprising from about 2 to about 10 wt. % multifunctional ethylenically unsaturated siloxane polymer, from about 2 to about 10 wt. % monofunctional ethylenically unsaturated siloxane macromer, and from about 85 to about 96 wt. % vinyl monomer. 
     
     
       2. The adhesive composition of  claim 1 , wherein the multifunctional ethylenically unsaturated siloxane polymer is represented by the formula: 
       
         
           
           
               
               
           
         
       
       wherein
 X is independently a monovalent group having vinyl functionality; 
 Y is independently a divalent linking group; 
 D is independently selected from the group consisting of hydrogen, an alkyl group having from about 1 to about 10 carbon atoms, aryl, and substituted aryl; 
 R is a divalent hydrocarbon group; 
 R 1  is independently selected from the group consisting of alkyl, substituted alkyl, aryl, and substituted aryl; 
 R 2  is independently selected from the group consisting of alkyl, substituted alkyl, aryl, and substituted aryl; 
 R 3  is independently selected from the group consisting of alkyl, substituted alkyl, aryl, substituted aryl, and vinyl; 
 R 4  is independently selected from the group consisting of alkyl, substituted alkyl, aryl, substituted aryl, and vinyl; 
 m is 0 or 1; and 
 n is an integer from about 15 to about 1000. 
 
     
     
       3. The adhesive composition of  claim 2 , wherein
 X is 
 
       
         
           
           
               
               
           
         
         Y is 
       
       
         
           
           
               
               
           
         
         D is hydrogen; 
         R is
   —CH 2 CH 2 CH 2 —;
 
 
         R 1 , R 2 , R 3 , and R 4  are —CH 3 ; 
         m is 1; and 
         n is an integer from about 15 to about 1000; and 
         X and Y form a methacrylate. 
       
     
     
       4. The adhesive composition of  claim 2 , wherein
 X is
   X=—CH═CH 2 ;
 
 
 Y is 
 
       
         
           
           
               
               
           
         
         D is hydrogen; 
         R is
   —CH 2 CH 2 CH 2 —;
 
 
         R 1 , R 2 , R 3 , and R 4  are —CH 3 ; 
         m is 1; and 
         n is an integer from about 15 to about 1000; and 
         X and Y form an acrylamide. 
       
     
     
       5. The adhesive composition of  claim 2 , wherein
 X is
   X=—CH═CH 2 ;
 
 
 D is hydrogen; 
 R is
   —CH 2 CH 2 CH 2 ;
 
 
 R 1 , R 2 , R 3 , and R 4  are —CH 3 ; 
 m is 0; and 
 n is an integer from about 15 to about 1000. 
 
     
     
       6. The adhesive composition of  claim 2 , wherein
 X is independently 
 
       
         
           
           
               
               
           
         
         Y is independently 
       
       
         
           
           
               
               
           
         
         D is hydrogen; 
         R is
   —CH 2 CH 2 CH 2 —;
 
 
         R 1 , R 2 , R 3 , and R 4  are —CH 3 ; 
         m is 0 or 1; 
         n is an integer from about 15 to about 1000; and 
         X and Y form either a (meth)acrylate or a (meth)acrylamide. 
       
     
     
       7. The adhesive composition of  claim 1 , wherein the monofunctional ethylenically unsaturated siloxane macromer has the formula: 
       
         
           
           
               
               
           
         
       
       wherein
 q is 0 or 1; 
 s is 1, 2, or 3; 
 r is an integer from about 15 to about 1000; 
 R 7  is a monovalent group selected from the group consisting of alkyl, substituted alkyl, alkoxy, alkyl amino, hydroxyl, aryl, and substituted aryl; 
 X is independently 
 
       
         
           
           
               
               
           
         
         Y is independently 
       
       
         
           
           
               
               
           
         
         D is independently selected from the group consisting of hydrogen, an alkyl group having from about 1 to about 10 carbon atoms, aryl, and substituted aryl; 
         R is a divalent hydrocarbon group; 
         R 2  is independently selected from the group consisting of alkyl, substituted alkyl, aryl, and substituted aryl; 
         R 3  is independently selected from the group consisting of alkyl, substituted alkyl, aryl, substituted aryl, and vinyl; 
         R 4  is independently selected from the group consisting of alkyl, substituted alkyl, aryl, substituted aryl, and vinyl; and 
         m is 0 or 1; 
         with the proviso that when q is 0, Y is 
       
       
         
           
           
               
               
           
         
       
       such that X and Y form a (meth)acrylate. 
     
     
       8. The adhesive composition of  claim 7 , wherein r is from about 120 to about 150. 
     
     
       9. The adhesive composition of  claim 7 , wherein r is from about 130 to about 135. 
     
     
       10. The adhesive composition of  claim 1 , wherein the vinyl monomer comprises a single monomer or a mixture of more than one monomer. 
     
     
       11. The adhesive composition of  claim 10 , wherein the vinyl monomer comprises a mixture of soft and hard monomers, wherein
 the soft monomer is a monomer that when homopolymerized, has a Tg of less than about 0° C., and 
 the hard monomer is a monomer that when homopolymerized, has a Tg of greater than about 0° C. 
 
     
     
       12. The adhesive composition of  claim 11 , wherein the soft monomer is an ester of acrylic acid comprising from about 5 to about 21 carbon atoms, an ester of methacrylic acid comprising from about 8 to about 22 carbon atoms, or a combination thereof. 
     
     
       13. The adhesive composition of  claim 12 , wherein the soft monomer is isooctyl acrylate, 2-ethylhexyl acrylate, butyl acrylate, 2-methylbutyl acrylate, 4-methyl-2-pentyl acrylate, sec-butyl acrylate, isononyl acrylate, isodecyl acrylate, or mixtures thereof. 
     
     
       14. The adhesive composition of  claim 11 , wherein the hard monomer is (meth)acrylic acid, a branched (meth)acrylate, a (meth)acrylate having from about 5 to about 7 carbon atoms, a vinyl ester of a carboxylic acid, a styrene derivative, a (meth)acrylamide derivative, an acrylonitrile derivative, or a combination thereof. 
     
     
       15. The adhesive composition of  claim 14 , wherein the hard monomer is cyclohexyl (meth)acrylate, isobornyl (meth)acrylate, t-butyl (meth)acrylate, vinyl acetate, isopropenyl acetate, styrene, vinyl toluene, hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate, N,N-dimethylacrylamide, (meth)acrylonitrile, N-vinyl pyrrolidone, N-vinyl caprolactam, vinylidene chloride, or a combination thereof. 
     
     
       16. The adhesive composition of  claim 1 , wherein the vinyl monomer comprises isooctyl (meth)acrylate, isobornyl (meth)acrylate, or a combination thereof. 
     
     
       17. An adhesive article comprising a first substrate having thereon an adhesive layer, wherein
 the adhesive layer comprises a cured adhesive composition of from about 2 to about 10 wt. % multifunctional ethylenically unsaturated siloxane polymer, from about 2 to about 10 wt. % monofunctional ethylenically unsaturated siloxane macromer, and from about 85 to about 96 wt. % vinyl monomer; and 
 the first substrate comprises a polymer film, paper, a metal film, glass, ceramic, or a combination thereof. 
 
     
     
       18. The adhesive article of  claim 17 , wherein the first substrate comprises a polarizing film, a prism film, a light guide, a diffusive film, a brightness enhancing film, a liquid crystal display, a glare control film, a transparent surface protective film, a privacy film, or a combination thereof. 
     
     
       19. The adhesive article of  claim 17 , further comprising a release liner adjacent the adhesive layer on the opposite side from the first substrate. 
     
     
       20. The adhesive article of  claim 19 , wherein the release liner is a microstructured release liner. 
     
     
       21. An optical device comprising the adhesive article of  claim 17 .